The Southern California office of architectural giant Gensler tops the list of the largest interior design firms in Los Angeles County. The firm generated $27.8 million in billings for interior design work performed locally during 2007. That’s up $3.5 million compared with the previous year.

One of the busiest sectors for Gensler in Los Angeles is the entertainment industry. It is currently designing new headquarters for the William Morris Agency after completing work for rival Creative Artists Agency at the 2000 Avenue of the Stars building in Century City.

At Sony’s lot in Culver City, Gensler is working on the new construction of two office buildings, a parking structure and digital studios. Gensler is also working on a project for DreamWorks Animation SKG.

In downtown, Gensler is working on the Ritz-Carlton Hotel at LA Live, part of the $2.5 billion Anschutz Entertainment Group development. Also in downtown, the firm designed a 300,000-square-foot office project for law firm Latham & Watkins LLP.

In the financial sector, Gensler’s local office has worked on projects for Ares Management and Cathay Bank. Other local projects include the Port of Los Angeles and electronics manufacturer Belkin Corp.

Gensler has 94 employees in its commercial interior design practice at its Santa Monica office.